Title : analysis of rosiglitazone in rabbit plasma by hptlc

Title :Analysis of Rosiglitazone in rabbit plasma by HPTLC Author(s) : *S. N. Meyyanathan, Bharani Pandilla, P. Ashok and B. Suresh *E Mail: [email protected]ABSTRACT:
A new simple, precise, rapid, and selective high-performance thin layer
chromatography (HPTLC) method was developed for the analysis of
Rosiglitazone in rabbit plasma. 2 mg and 4 mg of Rosiglitazone are commercially
available as tablets. Only HPLC methods have been reported for the above
mentioned drug in the literature and no HPTLC method is available for the
estimation in rabbit plasma. The method uses Losartan potassium as an internal
standard. The stationary phase used is RP-18 F254s HPTLC plate, prewashed
with methanol. The mobile phase consists of methanol : water (10.0 : 2.0 , v/v).
Detection and quantification are performed densitometrically at λ = 236 nm. The
Rf values of Rosiglitazone and Losartan potassium (IS) are 0.57, and 0.78,
respectively. The limits of detection of nimesulide and chlorzoxazone are 0.02
and 0.06 μg respectively. Linearity range for Rosiglitazone is 0.2 - 1.0 μg.
Healthy over night fasted animals were used for the experiments. Zero hour
fasting blood samples were with drawn early in the morning. The animals were
then divided into 3 groups of 6 animals each. The dose for the rabbits was
selected based on the surface area ratio of rabbit and man. Group I received
0.3% carboxymethyl cellulose as solvent control. Group 2 received rosiglitazone
pure drug and after a wash out period of 15 days group 1 and 2 received the
pharmaceutical preparations respectively. The pure drug and the pharmaceutical
preparation were suspended in 0.3% carboxy methyl cellulose and the
homogenous microsuspensions were administered orally. Immediately after
administration the animals were given 5ml of water. Blood samples (1ml each)
were with drawn from the marginal ear vein at intervals of 0.5, 1, 2, 3, 4, 6, 8 and
12 hours period using a sterilized syringe. The blood samples collected in the
centrifuge tube containing the anti coagulant (100 μl of 11% sodium citrate) were
centrifuged at 3000 rpm for 5 minutes and the plasma samples were separated
and stored at –20oC. The plasma samples were deproteinised by mixing the
sample with equal volume of acetonitrile and the contents were shaken well and
allowed to stand for 5 minutes. It was then centrifuged at 3000 rpm for 5 minutes
and the supernatant liquid was separated and analysed. Estimation of the
plasma samples by HPTLC was carried out using optimized chromatographic
conditions. The standard and sample solutions (20 μl) were spotted and the
chromatograms were recorded. The plasma drug concentration of the pure drug
and pharmaceutical preparations at different time intervals were calculated.
Pharmacokinetic parameters such as maximum blood level drug concentration
(Cmax), time to peak concentration (Tmax), area under the plasma concentration-
time curve (AUC0-12) were calculated. The comparative pharmacokinetic
parameters of pure drug and pharmaceutical preparations were calculated. When
compared to pure drug, the pharmaceutical preparations shows better
bioavailability which is indicated by increased AUC because of the presence of
formulation additives. The developed method was suitably validated. The
simplicity, accuracy, sensitivity and precision of the developed method makes it
as choice for routine analysis of Rosiglitazone in rabbit plasma.
Comparative pharmacokinetic parameters of pure drug and pharmaceutical preparations Pharmaco Pure drug Pharmaceutical preparations 2mg 4mg 2mg parameters Typical chromatogram of Rosiglitazone in rabbit plasma